error[E0499]: cannot borrow `list[_].value` as mutable more than once at a time --> $DIR/issue-62007-assign-const-index.rs:23:21 | LL | fn to_refs(mut list: [&mut List; 2]) -> Vec<&mut T> { | - let's call the lifetime of this reference `'1` ... LL | result.push(&mut list[0].value); | ^^^^^^^^^^^^^^^^^^ `list[_].value` was mutably borrowed here in the previous iteration of the loop ... LL | return result; | ------ returning this value requires that `list[_].value` is borrowed for `'1` error[E0499]: cannot borrow `list[_].next` as mutable more than once at a time --> $DIR/issue-62007-assign-const-index.rs:24:26 | LL | fn to_refs(mut list: [&mut List; 2]) -> Vec<&mut T> { | - let's call the lifetime of this reference `'1` ... LL | if let Some(n) = list[0].next.as_mut() { | ^^^^^^^^^^^^--------- | | | `list[_].next` was mutably borrowed here in the previous iteration of the loop | argument requires that `list[_].next` is borrowed for `'1` error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0499`.